cc: Dump scheduler and tile manager state when commit is blocked.

cc/trees/proxy_impl.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/trees/proxy_impl.h"
 
+#include <string.h>
+
 #include <algorithm>
 #include <string>
 
 #include "base/auto_reset.h"
+#include "base/debug/alias.h"
+#include "base/debug/dump_without_crashing.h"
 #include "base/memory/ptr_util.h"
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "base/trace_event/trace_event_synthetic_delay.h"
 #include "cc/base/devtools_instrumentation.h"
 #include "cc/benchmarks/benchmark_instrumentation.h"
 #include "cc/input/browser_controls_offset_manager.h"
 #include "cc/output/compositor_frame_sink.h"
 #include "cc/output/context_provider.h"
 #include "cc/scheduler/compositor_timing_history.h"
@@ skipping 195 matching lines @@
     bool* main_frame_will_happen) {
   DCHECK(IsImplThread());
   if (layer_tree_host_impl_->compositor_frame_sink()) {
     *main_frame_will_happen = scheduler_->MainFrameForTestingWillHappen();
   } else {
     *main_frame_will_happen = false;
   }
   completion->Signal();
 }
 
+// TODO(sunnyps): Remove this code once crbug.com/668892 is fixed.
+NOINLINE void ProxyImpl::DumpForBeginMainFrameHang() {
+  DCHECK(IsImplThread());
+  DCHECK(scheduler_);
+
+  char stack_string[20000] = "\0";

[vmpstr, 2017/04/11 01:06:46]

nit: = ""; (or = {}; or = {0};)

[sunnyps, 2017/04/11 18:22:48]

Done.

+  base::debug::Alias(&stack_string);
+
+  std::unique_ptr<base::trace_event::ConvertableToTraceFormat> scheduler_state =
+      scheduler_->AsValue();
+  strncat(stack_string, scheduler_state->ToString().c_str(),
+          arraysize(stack_string) - strlen(stack_string) - 1);
+
+  std::unique_ptr<base::trace_event::ConvertableToTraceFormat>
+      tile_manager_state =
+          layer_tree_host_impl_->tile_manager()->ActivationStateAsValue();
+  strncat(stack_string, tile_manager_state->ToString().c_str(),
+          arraysize(stack_string) - strlen(stack_string) - 1);
+
+  base::debug::DumpWithoutCrashing();
+}
+
 void ProxyImpl::NotifyReadyToCommitOnImpl(
     CompletionEvent* completion,
     LayerTreeHost* layer_tree_host,
     base::TimeTicks main_thread_start_time,
     bool hold_commit_for_activation) {
   TRACE_EVENT0("cc", "ProxyImpl::NotifyReadyToCommitOnImpl");
   DCHECK(!commit_completion_event_);
   DCHECK(IsImplThread() && IsMainThreadBlocked());
   DCHECK(scheduler_);
   DCHECK(scheduler_->CommitPending());
@@ skipping 413 matching lines @@
 ProxyImpl::BlockedMainCommitOnly& ProxyImpl::blocked_main_commit() {
   DCHECK(IsMainThreadBlocked() && commit_completion_event_);
   return main_thread_blocked_commit_vars_unsafe_;
 }
 
 base::SingleThreadTaskRunner* ProxyImpl::MainThreadTaskRunner() {
   return task_runner_provider_->MainThreadTaskRunner();
 }
 
 }  // namespace cc